• Journal of Plant Biology
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• 제28권4호
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• pp.329-332
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• 1985

A simple new device for obtaining very clear epidermal imprints for light microscopic studies is discussed. This new device is developed from“Britfix”(polystyrene cement) which is non-toxic to the plant organs. It involves direct application of the material on the desired surface of the plant organ to obtain thin, transparent replica. From the present investigation“Britfix”is found to be useful for the study of epidermal anatomy, morphology and physiology. Epidermal imprints can be mounted on the microscope slide without a mounting medium. Permanent slide of these imprints can be kept for any desired period without any deterioration of the replica.

• 대한원격탐사학회지
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• 제38권5_3호
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• pp.979-989
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• 2022

본 연구는 유독 와편모조류 Alexandrium pacificum의 조기 감지 여부를 조사하기 위해 홀 소자 센서(Hall element sensor)를 활용하여 진주담치(Mytilus edulis)와 참굴(Crassostrea gigas)의 패각운동(shell valve movements, SVMs) 변화를 살펴보았다. 무독성 조류 Isochrysis galbana에 대한 SVMs는 M. edulis와 C. gigas에서 모두 증감이 관찰되지 않았다. 하지만 마비성 패독(paralytic shellfish poisoning, PSP)을 유발하는 A. pacificum에 노출됨에 따라 M. edulis와 C. gigas는 폭로 전후로 약 12시간 동안 평균 SVMs가 각각 1.25 times/hr에서 2.13 times/hr 그리고 2.23 times/hr에서 8.91 times/hr로 증가하였다. M. edulis는 A. pacificum에 노출되고 1시간 이내에 SVMs가 증가한 뒤 점차 감소한 추세를 보였지만, C. gigas는 노출 후 4시간까지도 높은 SVMs를 보여, C. gigas가 M. edulis보다 유독 와편모조류에 대한 민감성이 높은 것으로 보였다. 따라서 이러한 결과들은 유독 와편모조류 A. pacificum의 출현 시 조기 감지를 할 수 있는 생물모니터링 시스템 체계 구축에 기초자료로 활용될 수 있을 것으로 기대된다.

• 한국양식학회:학술대회논문집
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• 한국양식학회 2003년도 추계학술발표대회 논문요약집
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• pp.132-133
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• 2003

The marine dinoflagellate genus Alexandrium comprise PSP producing A. acatenella, A. angustitabuzatum, A. catenella, A. fundyense, A. minutum, A. ostenfezdii, A. tamiyavanichii and A. tamarense. In monitoring toxic Alexandrium, rapid and exact species identification is one of the significant prerequisite work, however we have suffered confusion of species definition in Alexandrium. To surmount this problem, we chose DNA probing, which has long been used as an alternative for conventional identification methods, primarily relying on morphological approaches using microscope in microbial field. Oligonucleotide DNA probes targeting rRNA or rDNA have been commonly used in diverse studies to detect and enumerate cells concerned as a culture-indetendent powerful tool. Despite of the massive literature on the HAB species containing Alexandrium, application of DNA probing for species identification and detection has been limited to a few documents. DNA probes of toxic A. tamarense, A. catenella and A. tamiyavanichii, and non-toxic A. affine, A. fraterculus, A. insuetum and A. pseudogonyaulax were designed from LSU rDNA D1-D2, and applied to whole cell-FISH. Each DNA probes reacted only the targeted Alexandrium cells with very high species-specificity within Alexandrium. The probes could detect each targeted cells obtained from the natural sea water samples without cross-reactivity. Labeling intensity varied in the growth stage, this showed that the contents of probe-targeted cellular rRNA decreased with reduced growth rate. Double probe TAMID2S1 achieved approximately two times higher fluorescent intensity than that with single probe TAMID2. This double probe did not cross-react with any kinds of microorganisms in the natural sea waters. Therefore we can say that in whole-cell FISH procedure this double DNA probe successfully labeled targeted A. tamiyavanichii without cross-reaction with congeners and diverse natural bio-communities.

• 한국농공학회논문집
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• 제57권4호
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• pp.21-29
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• 2015

Safety of reclaimed wastewater irrigation needs to be evaluated to promote public health. Quantitative microbial and toxic risk assessment was conducted to identify the level of risk for farmland workers who use reclaimed wastewater and groundwater in Jeju island. Microbial risk through inhalation and ingestion exposure was below acceptable level (less than $10^{-3}$) of $7.07{\times}10^{-6}$ for reclaimed wastewater and $9.99{\times}10^{-8}$ for groundwater irrigation worker. Aggregate exposure risk of Ni, As and Cu was most contributable to overall risk in both reclaimed wastewater and groundwater irrigation plot. High cumulative exposure risk was estimated through non-dietary soil ingestion and dermal contact of soil, due to the high concentration of As, Cu and Ni in farmland soil. Overall toxic risk was $2.68{\times}10^{-4}$ for reclaimed water and $2.39{\times}10^{-4}$ for groundwater irrigation, which could not meet acceptable toxic risk level of $10^{-6}$. Further efforts, such as provide personal protective equipments or public health education, need to be implicated to reduce adverse health risk.

• 한국물환경학회지
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• 제34권1호
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• pp.77-83
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• 2018

This paper aims to evaluate the results of toxicity testing with Daphnia magna and Vibrio fischeri on wastewater samples which might be influenced by ion imbalance. The effluents from factories were found to be more toxic with high salinity levels than those from public wastewater treatment plant (WTP) and sewage treatment plant (SWP). Clion composition was highest in the effluent, in terms of percentage, which was followed by $Na^+$, $SO_4^{2-}$ and $Ca^{2+}$. $K^+$ and $Mg^{2+}$ ion was relatively low. The sensitivity of D. magna test results was higher than V. fischeri. Among samples which were proved by V. fischeri testing to be nontoxic, the composition ratio of each ion whether toxic samples or nontoxic samples which were decided by D. magna toxicity testing, were compared. $Na^+$, $K^+$, $Ca^{2+}$, $Mg^{2+}$ ion composition ratio showed high level in nontoxic samples whereas $SO_4^{2-}$ and $Cl^-$ ion composition ratio was high in toxic samples. Accordingly, $SO_4^{2-}$ and $Cl^-$ ion seemed to be considered the ions causing toxicity in effluent. Toxicity from some categories of industries (Mining of non-metallic minerals, Manufacture of basic organic petrochemicals, Manufacture of other basic organic chemicals, Manufacture of other chemical products etc.) seemed to be influenced by salinity. The Ion concentration in influent and effluent were similar. Concentration of $Na^+$, $Cl^-$, $K^+$, $Ca^{2+}$ ions were high in influent, however $Mg^{2+}$ and $SO_4^{2-}$ ions were high in effluent.

• Toxicological Research
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• 제31권1호
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• pp.41-48
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• 2015

Owing to the increase in price of cigarettes in Korea, herbal cigarettes have received increasing attention as a non-smoking aid; however, its safety has hardly been studied. We analyzed some of the toxic components in the mainstream smoke of herbal cigarettes, performed a mutagenicity test on smoke condensates for safety assessment, and compared the results with the corresponding values of a general cigarette with the same tar content. Herbal cigarette "A" was smoked using automatic smoking machine under ISO conditions in a manner similar to general cigarette "T". The tar content measured was higher than that inscribed on the outside of a package. The mainstream smoke of herbal cigarette "A" did not contain detectable levels of tobacco-specific nitrosamines and nicotine. Carbon monoxide and benzo(${\alpha}$)pyrene contents in herbal cigarette "A" were higher than those in the general cigarette "T". The phenolic contents such as hydroquinone, resorcinol, and catechol in herbal cigarette "A" were higher than those in the general cigarette "T", but cresol contents in herbal cigarette "A" were lower than those in the general cigarette "T". The content of aromatic amines such as 4-aminobiphenyl in herbal cigarette "A" was higher than that in the general cigarette "T"; however, this difference was not statistically significant. On the other hand, 1-aminonaphthalene, 2-aminonaphthalene, and 3-aminobiphenyl contents in herbal cigarette "A" were lower than those in the general cigarette "T". The smoke condensates of herbal cigarette "A" exhibited a higher mutagenic potential than the condensates from the general cigarette "T" at the same concentration. We concluded that the mainstream smoke of herbal cigarette contains some toxic components, the smoke condensates of herbal cigarettes are mutagenic similar to general cigarette because of combustion products, and that the evaluation of the chemical and biological safety of all types of herbal cigarettes available on the market.

• 자원환경지질
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• 제29권4호
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• pp.495-508
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• 1996

This study had three purposes: (1) to investigate dispersion and enrichment level of potentially toxic elements; (2) to identify uranium-bearing minerals in black shales; and (3) to assess the chemical speciation of heavy metals in soils and sediments. Rock, surface soil and stream sediment samples were collected in the Chungjoo area covered with black shales in Korea. These samples were analyzed for multi-elements using INAA and ICP-AES. The maximum abundance of U in black shales is 56 ppm and radioactivity counts up to 240CPM. Molybdenum, V, Ba, Cu, and Pb are enriched in black shales and most of soils show high concentrations of U, Mo, Ba, Cu, Pb and Zn. Concentrations of potentially toxic elements decrease in the order of mountain soil > farmland soil > paddy soil. Enrichment index of soils and sediments are calculated and higher than 1.0 in the black shale area with the highest value of 6.1. In order to identify U-bearing minerals, electron probe micro analysis was applied, and uraninite and brannerite in black shale were found. Uraninite grains are closely associated with monazite or pyrite with the size of $2{\mu}m$ to $10{\mu}m$ in diameter whereas brannerite occurs as $50{\mu}m$ euhedral grains. With the results of sequential extraction scheme, residual fractions of Cu, Pb and Zn in soils are mainly derived from weathering of black shale but Cu, Pb and Zn in sediments are present as non-residual fractions. Lead is predominantly present as oxidizable phase in soils whereas Zn is in exchageable/water-acid soluble phase in sediments.

• 약학회지
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• 제55권4호
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• pp.352-360
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• 2011

Standard combination chemotherapy including isoniazid, rifampin, pyrazinamide, and ethambutol is very effective against tuberculosis. But, these medicines can cause hepatotoxicity which is the main reason for treatment interruption or change in drug regimen. In order to identify risk factors associated with hepatotoxcity in Koreans and assess elevated baseline LFTs' contributions to hepatotoxicity, a retrospective case control study was performed. The medical records of 277 patients who diagnosed with tuberculosis at a community hospital from January 1st, 2007 to June 30th, 2010 were reviewed. Patients were categorized into 3 groups (non toxic group, patients without increase in LFT levels; mild to moderate hepatotoxic group and severe hepatotoxic group). And the correlation between risk factors and hepatotoxicity was analyzed by using SPSS program. The overall incidence of hepatotoxicity was 18% and 8.7% of patients developed severe toxicity. Patients in the severe toxic group had the longest treatment period among the three groups. In 75% of severe toxic group, hepatotoxicity occurred within 18.3 days after starting medication. Hypoalbuminemia (serum albumin <3 g/dl) was a significant risk factor for development of severe toxicity. Elevated baseline transaminase (except ALT), total bilirubin, and preexisting hepatitis were also risk factors which were more than twice as likely to increase risk of severe hepatotoxicity (p>0.05). In conclusion, hypoalbuminemia (serum albumin level <3 g/dl) was a significant risk factor for anti-tuberculosis druginduced severe toxicity. Therefore, before starting antituberculosis chemotherapy, serum albumin level should be assessed at baseline. In high-risk patients (hypoalbuminemia, elevated LFTs) for hepatotoxicty, liver function should be closely monitored up to at least 21 days after taking medication.

• 생태와환경
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• 제49권4호
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• pp.393-399
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• 2016

국내 주요 상수원지 (영천호, 안계호, 가창호)에서 분리한 6종의 Microcystis (M. aeruginosa, M. ichthyoblabe, M. flos-aquae, M. novacekii, M. viridis 및 M. wesenbergii)를 대상으로 microcystin 생성유전자(mcy gene) 함유률 및 생성률을 조사하였다. 조사 결과에서 M. aeruginosa는 80%(55개 균주)가 mcy gene을 함유하고 있었으며, 그 다음으로 M. ichthyoblabe는 45% (10개 균주)의 함유율을 나타내었다. 그 외에 M. flos-aquae와 M. wesenbergii는 각각 11%(4개 균주)와 33% (1개 균주)가 microcystin 생성유전자를 포함하였다. 6종의 Microcystis에서 mcy gene의 함유율은 실제 microcystin 생성율과 거의 일치하였다. 특히, 가장 많은 균주에서 mcy gene이 확인된 M. aeruginosa는 대부분 균주들(75%)이 실제로 microcystin을 생성하는 것으로 조사되었다.

• Toxicological Research
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• 제35권1호
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• pp.1-7
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• 2019

Mycotoxin contamination is a global phenomenon and causes a wide array of negative effects and other complications. This study focused on commonly found mycotoxins in Africa and the possible means of prevention or reduction of their contaminating effects. Mycotoxins are secondary metabolites of mold and fungi; they are generally toxic to living organisms. Hundreds of mycotoxins have been identified thus far, with some, such as aflatoxins, ochratoxins, trichothecenes, zearalenone, fumonisins, and patulin, considered agro-economically important. Several factors contribute to the presence of mycotoxins in food, such as climatic conditions, pest infestation, and poor harvest and storage practices. Exposure to mycotoxins, which occurs mostly by ingestion, leads to various diseases, such as mycotoxicoses and mycoses that may eventually result in death. In light of this, this review of relevant literature focuses on mycotoxin contamination, as well as various methods for the prevention and control of their prevalence, to avert its debilitating consequences on human health. Clear evidence of mycotoxin contamination is present in Africa, and it was therefore recommended that adequate prevention and control of these toxic substances in our food system should be encouraged and that appropriate measures must be taken to ensure food safety as well as the enhanced or long-lifespan of the African populace. Governments, research institutions, and non-governmental organizations should tailor the limited resources available to tackle mycotoxin prevalence, as these will offer the best prospects for successful development of a sustainable food system in Africa.